Electricity prices tumbled across the West this week until warmer weather in California and the Southwest forced prices to diverge. Temperatures in the Golden State this Sunday are expected to make it one of the hottest days so far this year and drive up demand for power. Average peak prices cleared $100 at major trading centers in Arizona and California.

But in the Pacific Northwest, prices fell from $2 to $8 for both day and nighttime power as the region warmed up and emerged from rain and snow. One theory is that hydropower production may have driven down prices there, though other reports indicate that the snowmelt and spring runoff have been delayed. The year has been a snowy one for the region and more water than normal is expected to flow into area dams and reservoirs this spring.

At the California-Oregon border, average peak prices fell $16 by Wednesday to a week's low of $81.37, but perked up to settle Friday at an average of $95.23/MWh. Off-peak prices had the same pattern, drifting down $12 on Wednesday to $70.04, but closing Friday around $80.65/MWh.

Peak values at Mid-Columbia found a nadir of $77.84 on Thursday, but regained strength Friday to close at $89.24/MWh. Average nighttime prices skidded $15 by Thursday to $72.13, then rose to an average of $79.07 the next day.

Outside the Pacific Northwest, prices fell throughout the week only to soar Friday on weekend high-temperature predictions for California.

Peak electricity at North of Path 15 shed $10 by Thursday to rest at an average of $89.68, before it skyrocketed to close around $102.21/MWh. Off-peak average prices shed $6 to $71.97 on Wednesday, before rising Friday to around $83.50/MWh.

South of Path 15 prices were nearly identical to NP15's, though peak values hit a Western-hub high of $112/MWh on Friday.

Palo Verde peak power slid Wednesday to around $87.01, down from $94.37, and then shot up to an average of $100.19/MWh. Off-peak prices tumbled Thursday $5 to $66.79, then gained ground Friday to average $81.41/MWh.

Temperatures will be above average along the West Coast this weekend, with Seattle and Portland finally enjoying sunny skies and temperatures in the high 60s. By late Sunday, however, a storm from Alaska will bring rain and cooler temperatures to the region.

San Francisco temperatures this weekend will be in the low 70s, but will drift down to the more seasonal low 60s on Monday. In Southern California and Arizona, hot air from the Four Corners region will push temperatures into the high 80s and 90s, according to AccuWeather, but the mercury will fall back to the low 70s early next week.

Since hitting a high of 30,400 MW on Tuesday, demand on the California grid has remained below 30,000 MW this week
[Kristina Shevory].

The Western United States also saw a rise, with storage inching up 5 Bcf to 181 Bcf. Compared to last year, levels are about 28 percent lower in the West and 15 percent less than the five-year average.

The supply uptick didn't much move prices, which gained between 4 cents and 20 cents for the week. Values ranged from an average of $9.59/MMBtu Friday at the San Juan hub to $10.80/MMBtu at Pacific Gas & Electric's CityGate hub.

The U.S. EIA reports that high natural gas prices remain buttressed by fewer imports of liquefied natural gas, since U.S.-bound tankers are being diverted to Europe as the euro strengthens against the dollar. Looking ahead, natural gas prices may also remain high going into the summer because cooler temperatures in the Pacific Northwest have delayed the snowmelt. More gas will be used to generate power until hydroelectric production ramps up, according to the EIA
[K. S.].

Western Electricity Prices
Week's End: April 21 - 25, 2008

Hub

Peak (heavy)

Off-peak (light)

Alberta Pool (C$)

69.20 - 497.50

54.86 - 502.85

Mid-Columbia

76 - 100

71 - 90.25

COB

78.50 - 99

69.25 - 85.75

NP 15

88.75 - 107.90

71 - 87

SP 15

88.90 - 112

70.25 - 86.75

Palo Verde

84.75 - 105.75

64 - 82

Archives of the Western Price Survey for the past year are also available online.

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